/Engine/Source/Runtime/Engine/Public/HLSLTree/HLSLTree.h
Allows custom objects to be passed to custom HLSL functions. This needs to initialize some HLSL code that facilitates this interface. If this returns 'true', thenEmitValueShader()will be called to generate the actual HLSL code for theFExpression
virtual bool EmitCustomHLSLParameter ( [FEmitContext](API\Runtime\Engine\HLSLTree\FEmitContext) & Context, [FEmitScope](API\Runtime\Engine\HLSLTree\FEmitScope) & Scope, const [FName](API\Runtime\Core\UObject\FName) & ObjectTypeName, const TCHAR * ParameterName, [FEmitCustomHLSLParameterResult](API\Runtime\Engine\HLSLTree\FEmitCustomHLSLParameterResult) & OutResult ) const